Composite foam panels have been widely used in the building of wall and roof structures due to their high strength to weight ratio and insulative properties. These panels generally range in thickness from one inch to eight inches, depending upon load and thermal insulation requirements. Such panels commonly are fabricated in widths ranging generally from twelve inches to forty-eight inches.
Composite foam panels are generally fastened to building frame members such as horizontal wall girts and roof purlins in a side by side fashion to form the wall or roof surface. Obviously, concealed fastening systems are preferred by architects in order to present a smooth exterior surface.
Concealed fastening systems are generally of two types. The first, commonly designated as a metal skin interlocking design employs interlocking male and female side joints which are profiled along the side edges of the metal skins. The interior side joint is offset from the side edge of the exterior skin giving open accessibility for applying fasteners from the exterior side of the panel. The fastening system is then concealed by the exterior panel surface of the adjacent panel upon side joint engagement. In this type of design, each panel is fastened to the building frame along one side and engaged along the other side. In order to facilitate ease of engagement, a side joint cavity is provided for hiding the fastening system and for providing clearance within the engaged side joints.
The major drawback of the metal skin interlocking side joint design of the prior art is that thermal leakage through the side joint is inevitable. This is due to the presence of the side joint cavity, relative side joint movement under load and the through-conductivity of the fastening system. As such, this type of design is not suitable where thermal efficiency is the primary design function such as in a refrigeration building design.
The second commonly employed configuration is known as the foam core interlocking side joint design. Interlocking tongue and groove elements are provided along the side edges of the foam core. Spaced apart metal straps with mechanical interlocking devices are buried within the foam core of the panel for tightly interlocking the side joints. The panels are fastened to the building frame from the interior side using rivets.
Thermal leakage through panels constructed employing the referenced foam core interlocking side joint design is minimal and, as such, this type of panel is widely used in the construction of refrigeration buildings. However, this design is not without its drawbacks. More specifically, high construction costs are incurred and, in addition, extremely rigid tolerance control must be exercised during erection. These panels also present potential water leakage problems due to the lack of shielded pressure equalized cavities while, often times, interior accessability is not available for driving the rivets. Obviously, high erection costs result which is a problem exacerbated by the need for split crews, one outside crew for handling and placing the panels and one inside crew for interlocking side joints and fastening the panels to the appropriate supports.
Prior art panel designs have also been found to be extremely difficult to replace in situations where individual panel members are damaged for it is difficult to dismount and reassemble the panels in light of the interlocking side joints and lack of accessibility to the concealed fasteners.
Thus, an object of the present invention is to provide building panel members and building panel assemblies which do not suffer from the disadvantages recited previously.
It is still a further object of the present invention to provide panel members and building panel assemblies which are easy to erect while displaying excellent insulative properties, are resistent to water penetration and which employ concealed fasteners.